/**
 * @license Copyright (c) 2003-2023, CKSource Holding sp. z o.o. All rights reserved.
 * For licensing, see LICENSE.md or https://ckeditor.com/legal/ckeditor-oss-license
 */
/* globals window, document */
/**
 * @module adapter-ckfinder/utils
 */
const TOKEN_COOKIE_NAME = 'ckCsrfToken';
const TOKEN_LENGTH = 40;
const tokenCharset = 'abcdefghijklmnopqrstuvwxyz0123456789';
/**
 * Returns the CSRF token value. The value is a hash stored in `document.cookie`
 * under the `ckCsrfToken` key. The CSRF token can be used to secure the communication
 * between the web browser and the CKFinder server.
 */
export function getCsrfToken() {
    let token = getCookie(TOKEN_COOKIE_NAME);
    if (!token || token.length != TOKEN_LENGTH) {
        token = generateToken(TOKEN_LENGTH);
        setCookie(TOKEN_COOKIE_NAME, token);
    }
    return token;
}
/**
 * Returns the value of the cookie with a given name or `null` if the cookie is not found.
 */
export function getCookie(name) {
    name = name.toLowerCase();
    const parts = document.cookie.split(';');
    for (const part of parts) {
        const pair = part.split('=');
        const key = decodeURIComponent(pair[0].trim().toLowerCase());
        if (key === name) {
            return decodeURIComponent(pair[1]);
        }
    }
    return null;
}
/**
 * Sets the value of the cookie with a given name.
 */
export function setCookie(name, value) {
    document.cookie = encodeURIComponent(name) + '=' + encodeURIComponent(value) + ';path=/';
}
/**
 * Generates the CSRF token with the given length.
 */
function generateToken(length) {
    let result = '';
    const randValues = new Uint8Array(length);
    window.crypto.getRandomValues(randValues);
    for (let j = 0; j < randValues.length; j++) {
        const character = tokenCharset.charAt(randValues[j] % tokenCharset.length);
        result += Math.random() > 0.5 ? character.toUpperCase() : character;
    }
    return result;
}
